aiu.eduaiu.edu/.../upload/1-1282013-72310-876158505.docx · Web viewIn portable or battery-powered systems this can limit use of digital systems. Digital circuits are sometimes more

1

ADRIANO PEDRO RODRIGUES

ID UB18207SSO26040

COURSE TITLE ELECTRONIC ENGINEERING

Index

1- Introductionhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag 5

1- Electronic engineeringhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag 6

11-History of electronic engineeringhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag 6

12-The vacuum tube detectorhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag 7

13-History of computing hardwarehelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag 7

14-Desktop calculatorshelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag 9

15-Digital computationhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag 9

16-Comercial computershelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag11

17-Microprocessorshelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag12

18-Electromagnetism amp photoelectric effecthelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag13

181-Historyhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag13

182- Classical electromagnetismhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag14

183-Electromagnetic waveshelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag14

184-Introduction and early historical viewhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag14

185-Traditional explanationhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag15

186-Stoletov The first law of photoeffecthelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag15

187-Einstein light quantahelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag16 188-Uses and effectshelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag16 189-Photoelectron spectroscopyhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag16

1810-Cross sectionhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag17

1811-Electromagnetism unitshelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag17

1812-Electromagnetic phenomenahelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag17

1813-Electronic devices and circuitshelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag17

2

1814-Analog circuitshelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag17

1815-Digital circuitshelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag18

2-Signal processing telecommunications engineering amp control engineering pg18

21-Signal processinghelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag18

22-Categories of signal processinghelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag18

23-Telecommunications engineeringhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag19

24-Telecom equipment engineerhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag19

25-Control engineeringhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag19

26-Instrumentation engineering amp Computer engineeringhelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag20

27-Computer systems engineeringhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag21

28-Algorithmhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag21

29-Formalizationhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag21

210-Expressing algorithmshelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag22

211-Computer algorithmhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag22

212-Algorithm analysishelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag22

213-Manipulation of symbolshelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag24

214-Mathematics during the 1800s up to the mid- 1900shelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag24

215-Design methodshelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag25

216-Electrical lawshelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag25

217-Databasehelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag25

218-Database management systemhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag25

219-Applications of databaseshelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag26

220-Digital electronichelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag27

221-Advantageshelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag27

222-Disadvantageshelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag27

223-Analog issues in digital circuitshelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag27

224-Struture of digital systemhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag28

225-Design of testabilityhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag29

226-Logic familieshelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag29

227-Embebed systemshelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag30

3

228-CPU platformshelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag30

229-Debugginghelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag31

3Applications and basic principles of absorbershelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag32

31-Reverberation controlhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag32

32-Echo control in auditoria and lecture theatreshelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag34

33-Impedance admittance reflection coefficient and absorptionhelliphelliphelliphelliphelliphelliphellippag34

34-Natural noise controlhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag35

35-Loudspeaker cabinethelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag35

36-Echo control in auditoriahelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag36

37-Wavefronts and diffusers reflectionshelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag36

38-Burring the focusing from concave surfaceshelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag37

39-Measurements of absorbers propertieshelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag37

391-Porous absoptionhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag38

392-Resonant absorbrshelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag38

393-Helmholtz resonatorhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag39

394-Active absorption in tree dimensionshelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag40

395-Active diffusershelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag40

396-Controllershelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag41

4-Acoustic an introductionhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag41

41-Geometric room acoustichelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag41

42-Diffuse sound fieldhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag42

43-Energy density and reverberationhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag43

44-Electroacoustic transducershelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag44

45-Piezoelectric transducerhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag44

46-Electrostatic transducerhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag45

47-Magnetic transducerhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag45

48-Microphoneshelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag45

49-Condeser microphoneshelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag46

410-Piezoelectric microphoneshelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag46

411-Dynamic microphoneshelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag46

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412-Carbone microphoneshelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag47

413-Hidrophoneshelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag47

414-Loudspeaker and other electroacoustic sound sourceshelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag47

4141-Dynamic loudspeakerhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag47

4142-Electrostatic or condenser loudspeakerhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag47

4143-Magnetic loudspeakerhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag47

4144-The closed loudspeaker cabinethelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag47

4145-The bass-reflex cabinethelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag48

4146-Horn loudspeakerhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag48

4147-Loudspeaker directivityhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag48

5General analysishelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag49

6Conclusionhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag50

7Bibliographyhelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphelliphellippag51

5

INTRODUCTION

Electronic Engineering

Is an engineering discipline which uses the scientific knowledge of the behavior and effects of electrons to develop components devices systems or equipment (as in electron tubes transistors integrated circuits and printed circuit boards) that uses electricity as part of its driving force In our work on electronic engineering we present our acquired knowledge by making mention of the themes and issues that we find extremely important and is essential in the evaluation show that the job can haveApart from the historical aspects of temperament various topics are also addressed issues relating to the development of new technologies as well as formulas and calculations that contributed to the development and certification of these technologiesWe all know how important the role that engineering electro electronics has played in our daily lives to the point of being present in almost all branches of human activity primarily in the communications information and productionIn this work special attention is given to topics that address issues and knowledge that relate to the chosen course (sound engineering) that because it is a very comprehensive is sustained mainly by electronics construction innovation sensitivity etcThe use and development of new technologies is making life easier for itms that are linked to communication and media events in generalNow in this case the sound is something that accompanies us throughout our life since the alarm clock that wakes us in the morning to noticeable various sounds that surround us and that we transmit sound images of what surrounds us and which relates with all human activityThere are countries where we can hardly feel in calm environments as human activity and not only cause stress and consequently health problems to the population

Adriano Pedro Rodrigues

2013-01-21

6

ENGINEERING

11Electronic Engineering is an engineering discipline which uses the scientific knowledge of the behavior and effects of electrons to develop components devices systems or equipment (as in electron tubes transistors integrated circuits and printed circuit boards) that uses electrictity as part of its driving force

That encompasses many subfields including those that deal with power instrumentation engineering telecommunications and semiconductor circuit design amongst many othersThe name electrical engineering is still used to cover electronic engineering amongst some of the older (notably American) universities and graduates there are called electrical engineers The distinction between electronic and electrical engineers is becoming moreand more distinct While electrical engineers utilize voltage and current to deliver power electronic engineers utilize voltage and current to deliver information through information technology11 History of ElectronicEngineeringElectronic engineering as a profession sprang from technological improvements in the telegraph industry in the late 1800s and the radio and the telephone industries in the early 1900s People were attracted to radio by the technical fascination it inspired first in receiving and then in transmittingIn 1948 came the transistor and in 1960 the IC to revolutionize the electronic industry In the UK the subject of electronic engineering became distinct from electrical engineering as a university degree subject around 1960

Early electronics

1896 Marconi patente

In 1893 Nikola Tesla made the first public demonstration of radio communicationThe Franklin Institute in Philadelphia and the National Electric Light Association he described and demonstrated in detail the principles of radio communication In 1896 Guglielmo Marconi went on to develop a practical and widely used radio system In 1904 John Ambrose Fleming the first professor of electrical Engineering at University College London invented the first radio tube the diode

7

In 1906 Robert von Lieben and Lee De Forest independently developed the amplifier tube called the triodeVacuum tubes remained the preferred amplifying device for 40 years until researchers working for William Shockley at Bell Labs invented the transistor in 1947 In the following years transistors made small portable radios or transistor radios possible as well as allowing more powerful mainframe computers to be built Transistors were smaller and required lower voltages than vacuum tubes to workThe terms wireless and radio were then used to refer to anything electronic

Before the invention of the integrated circuit in 1959 electronic circuits were constructed from discrete components that could be manipulated by hand Non-integrated circuits consumed much space and power were prone to failure and were limited in speed although they are still common in simple applications By contrast integrated circuits packed a large number mdash often millions mdash of tiny electrical components mainly transistors into a small chip around the size of a coin12 The vacuum tube detector

The invention of the triode amplifier generator and detector made audio communication by radio practical Through the mid 1920s the most common type of receiver was the crystal set In the 1920s amplifying vacuum tubes revolutionized both radio receivers and transmittersIn 1928 Philo Farnsworth made the first public demonstration of purely electronic televisionOne of the latest and most advance technologies in TV screensdisplays has to do entirely with electronics principles and itrsquos the OLED (organic light emitting diode) displays and itrsquos most likely to replace LCD and Plasma technologiesDuring World War II many efforts were expended in the electronic location of enemy targets and aircraft These included radio beam guidance of bombers electronic counter measures early radar systems etc During this time very little if any effort was expended on consumer electronics developments13 History of computing hardware

The elements of computing hardware have undergone significant improvement over their history This improvement has triggered worldwide use of the technology performance has improved and the price has declined Computers are accessible to ever-increasing sectors of the worlds population Computing hardware has become a platform for uses other than computation such as automation communication control entertainment and educationThe von Neumann architecture unifies current computing hardware implementations The history of computer data storage is tied to the development of computers The major elements of computing hardware implement abstractions input output memory and processor A processor is composed of control and datapath In thevon Neumann architecture control of the datapath is stored in memory This allowed control to become an automatic process the datapath could be under software control perhaps in response to events

8

Analog computers have used lengths pressures voltages and currents to represent the results of calculations Eventually the voltages or currents were standardized and then digitized Digital computing elements have ranged from mechanical gears to electromechanical relays to vacuum tubes to transistors and to integrated circuits all of which are currently implementing the von Neumann architecture

The castle clock an astronomical clock invented by Al-Jazari in 1206 is considered to be the earliest programmable analog computerYazu Arithmometer Patented in Japan in 1903 Note the lever for turning the gears of the calculatorGerman polymath Wilhelm Schickard built the first digital mechanical calculator in 1623 and thus became the father of the computing eraLeibniz also described the binary numeral system a central ingredient of all modern computers However up to the 1940s many subsequent designs (including Charles Babbages machines of the 1800s and even ENIAC of 1945) were based on the decimal system Yazu Arithmometer in 1903 It consisted of a single cylinder and 22 gears and employed the mixed base-2 and base-5 number system familiar to users to the soroban (Japanese abacus)In 1835 Babbage described his analytical engine It was the plan of a general-purpose programmable computer employing punch cards for input and a steam engine for power

IBM 407 tabulating machine (1961)

A reconstruction of the Difference Engine II an earlier more limited design has been operational since 1991 at the London Science Museum With a few trivial changes it works as Babbage designed it and shows that Babbage was right in theoryHolleriths company eventually became the core of IBM IBM developed punch card technology into a powerful tool for business data- rocessing and produced an extensive line of unit record equipment By 1950 the IBM card had become ubiquitous in industry and governmentThe Thomas J Watson Astronomical Computing Bureau Columbia University performed astronomical calculations representing the state of the art in computingThe computer users for example science and engineering students at universities would submit their programming assignments to their local computer center in the form of a stack of cards one card per program line

9

Punched cards are still used and manufactured to this day and their distinctive dimensions (and 80-column capacity) can still be recognized in forms records and programs around the world

14 Desktop calculatorsCompanies like Friden Marchant Calculator and Monroe made desktop mechanical calculators from the 1930s that could add subtract multiply and divideOver time during the 1950s and 1960s a variety of different brands of mechanical calculator appeared on the market The first allelectronicdesktop calculator was the British ANITA MkVII which used a Nixie tube display and 177 subminiature thyratron tubes

Advanced analog computers

Before World War II mechanical and electrical analog computers were considered the state of the art and many thought they were the future of computingUnlike modern digital computers analog computers are not very flexible and need to be reconfigured (ie reprogrammed) manually to switch them from working on one problem to another Analog computers had an advantage over early digital computers in that they could be used to solve complex problems using behavioral analogues while the earliest attempts at digital computers were quite limitedBut as digital computers have become faster and use larger memory (for example RAM or internal storage) they have almost entirely displaced analog computers 15 Digital computationThe era of modern computing began with a flurry of development before and during World War II as electronic circuit elements replaced mechanical equivalents and digital calculations replaced analog calculations Machines such as the Z3 the AtanasoffndashBerry Computer the Colossus computers and the ENIAC were built by hand using circuits containing relays or valves (vacuum tubes) and often used punched cards or punched paper tape for input and as the main (non-volatile) storage mediumFor a computing machine to be a practical general-purpose computer there must be some convenient read-write mechanism punched tape for example

10

Nine-track magnetic tape

For a computing machine to be a practical general-purpose computer there must be some convenient read-write mechanism punched tape for exampleJohn von Neumann defined an architecture which uses the same memory both to store programs and data virtually all contemporary computers use this architecture (or some variant) While it is theoretically possible to implement a full computer entirely mechanically (as Babbages design showed) electronics made possible the speed and later the miniaturization that characterize modern computersGeorge Stibitz is internationally recognized as one of the fathers of the modern digital computer While working at Bell Labs in November 1937 Stibitz invented and built a relay-based calculator that he dubbed the Model K (for kitchen table on which he had assembled it) which was the first to calculate using binary formThe Atanasoff-Berry Computer was the worlds first electronic digital computer The design used over 300 vacuum tubes and employed capacitors fixed in a mechanically rotating drum for memory Though the ABC machine was not programmable it was the first to use electronic tubes in an adder

ENIAC

The US-built ENIAC (Electronic Numerical Integrator and Computer) was the first electronic general-purpose computer It combined for the first time the high speed of electronics with the ability to be programmed for many complex problemsThe computer MESM (МЭСМ Small Electronic Calculating Machine) became operational in 1950 It had about 6000 vacuum tubes and consumed 25 kW of power It could perform approximately 3000 operations per second

16 Commercial computers

11

IBM introduced a smaller more affordable computer in 1954 that proved very popularThe IBM 650 weighed over 900 kg the attached power supply weighed around 1350 kg The first transistorized computer was built at the University of Manchester and was operational by 1953 The bipolar junction transistor (BJT) was invented in 1947 If no electrical current flows through the base-emitter path of a bipolar transistor the transistors collector-emitter path blocks electrical current (and the transistor is said to turn full off) If sufficient current flows through the base-emitter path of a transistor that transistors collector-emitter path also passes current (and the transistor is said to turn full on) Current flow or current blockage represent binary 1 (true) or 0 (false) respectively From 1955 onwards bipolar junction transistors replaced vacuum tubes in computer designs giving rise to the second generation of computers Compared to vacuum tubes transistors have many advantages they are less expensive to manufacture and are much faster switching from the condition 1 to 0 in millionths or billionths of a second Transistor volume is measured in cubic millimeters compared to vacuum tubes cubic centimeters Transistors lower operating temperature increased their reliability compared to vacuum tubesTransistorized computers could contain tens of thousands of binary logic circuits in a relatively compact spaceTransistors greatly reduced computers size initial cost and operating costTypically second-generation computers were composed of large numbers of printed circuit boards such as the IBM Standard Modular System each carrying one to four logic gates or flip-flops

RAMAC DASDThe second generation disk data storage units were able to store tens of millions of letters and digits Multiple Peripherals can be connected to the CPU increasing the total memory capacity to hundreds of millions of charactersDuring the second generation remote terminal units (often in the form of teletype machines like a Friden Flexowriter) saw greatly increased use Telephone connections provided sufficient speed for early remote terminals and allowed hundreds of kilometers separation between remote-terminals and the computing center Eventually these standalone computer networks would be generalized into an interconnected network of networksmdashthe Internet

12

Intel 8742 eight-bit microcontroller IC

The explosion in the use of computers began with third-generation computers making use of Jack St Clair Kilbys and Robert Noyces independent invention of the integrated circuit (or microchip) which later led to the invention of the microprocessor by Ted Hoff Federico Faggin and Stanley Mazor at IntelAs late as 1975 Sperry Univac continued the manufacture of second-generation machines such as the UNIVAC 494 The Burroughs large systems such as the B5000 were stack machines which allowed for simpler programming These pushdown automatons were also implemented in minicomputers and microprocessors later which influenced programming language designMinicomputers served as low-cost computer centers for industry business and universitiesMicrocomputers the first of which appeared in the 1970s became ubiquitous in the 1980s and beyond Steve Wozniak co-founder of Apple Computer is credited with developing the first mass-market home computersIn the twenty-first century multi-core CPUs became commercially availableWhen the CMOS field effect transistor-based logic gates supplanted bipolar transistors computer power consumption could decrease dramatically (A CMOS Field-effect transistor only draws significant current during the transition between logic states unlike the substantially higher (and continuous) bias current draw of a BJT) This has allowed computing to become a commodity which is now ubiquitous embedded in many forms from greeting cards and telephones to satellitesThe arithmetic performance of these machines allowed engineers to develop completely new technologies and achieve new objectives Early examples include the Apollo missions and the NASA moon landingThe invention of the transistor in 1947 by William B Shockley John Bardeen and Walter Brattain opened the door for more compact devices and led to the development of the integrated circuit in 1959 by Jack Kilby

17 Microprocessors

The first PC was announced to the general public on the cover of the January 1975 issue of Popular ElectronicsIn the field of electronic engineering engineers design and test circuits that use the electromagnetic properties of electrical components such as resistors capacitors inductors diodes and transistors to achieve a particular functionality The tuner circuit

13

which allows the user of a radio to filter out all but a single station is just one example of such a circuitIn designing an integrated circuit electronics engineers first construct circuit schematics that specify the electrical components and describe the interconnections between themIntegrated circuits and other electrical components can then be assembled on printed circuit boards to form more complicated circuits Today printed circuit boards are found in most electronic devices including televisions computers and audio players

18 Electromagnetism amp Photoelectric Effect

Electromagnetism is the physics of the electromagnetic field a field that exerts a force on particles with the property of electric charge and is reciprocally affected by the presence and motion of such particlesA changing magnetic field produces an electric field (this is the phenomenon of electromagnetic induction the basis of operation for electrical generators induction motors and transformers) Similarly a changing electric field generates a magnetic fieldThe magnetic field is produced by the motion of electric charges ie electric currentThe magnetic field causes the magnetic force associated with magnetsThe theoretical implications of electromagnetism led to the development of special relativity by Albert Einstein in 1905 and from this it was shown that magnetic fields and electric fields are convertible with relative motion as a four vector and this led to their unification as electromagnetism181 History

While preparing for an evening lecture on 21 April 1820 Hans Christian Oslashrsted developed an experiment that provided surprising evidence As he was setting up his materials he noticed a compass needle deflected from magnetic north when the electric current from the battery he was using was switched on and off This deflection convinced him that magnetic fields radiate from all sides off of a wire carrying an electric current just as light and heat do and that it confirmed a direct relationship between electricity and magnetismOslashrsteds discovery also represented a major step toward a unified concept of energyThis unification which was observed by Michael Faraday extended by James Clerk Maxwell and partially reformulated by Oliver Heaviside and Heinrich Hertz is one of the accomplishments of 19th century Mathematical PhysicsDifferent frequencies of oscillation give rise to the different forms of electromagnetic radiation from radio waves at the lowest frequencies to visible light at intermediate frequencies to gamma rays at the highest frequenciesOslashrsted was not the only person to examine the relation between electricity and magnetism In 1802 Gian Domenico Romagnosi an Italian legal scholar deflected a magnetic needle by electrostatic charges Actually no galvanic current existed in the setup and hence no electromagnetism was presentThe force that the electromagnetic field exerts on electrically charged particles called the electromagnetic force is one of the fundamental forces The other

14

fundamental forces are strong nuclear force (which holds atomic nuclei together) the weak nuclear force andthe gravitational force All other forces are ultimately derived from these fundamental forcesThe electromagnetic force is the one responsible for practically all the phenomena encountered in daily life with the exception of gravity All the forces involved in interactions between atoms can be traced to the electromagnetic force acting on the electrically charged protons and electrons inside the atomsIt also includes all forms of chemical phenomena which arise from interactions between electron orbitals182 Classical electromagnetism

Classical electromagnetism (or classical electrodynamics) is a branch of theoretical physics that studies consequences of the electromagnetic forces between electric charges and currents It provides an excellent description of electromagnetic phenomena whenever the relevant length scales and field strengths are large enough that quantum mechanical effects are negligible (see quantum electrodynamics)The outstanding problem with classical electrodynamics as stated by Jackson is that we are able to obtain and study relevant solutions of its basic equations only in two limiting cases raquo one in which the sources of charges and currents are specified and the resulting electromagnetic fields are calculated and the other in which external electromagnetic fields are specified and the motion of charged particles or currents is calculated Occasionallythe two problems are combined183 Electromagnetic waves

A changing electromagnetic field propagates away from its origin in the form of a waveThese waves travel in vacuum at the speed of light and exist in a wide spectrum of wavelengths Examples of the dynamic fields of electromagnetic radiation (in order of increasing frequency) radio waves microwaves light (infrared visible light and ultraviolet) x-rays and gamma rays In the field of particle physics this electromagnetic radiation is the manifestation of the electromagnetic interaction between charged particlesPhotoelectric effectThe photoelectric effect is a phenomenon in which electrons are emitted from matter (metals and non-metallic solids liquids or gases) after the absorption of energy from electromagnetic radiation such as X-rays or visible light The emitted electrons can be referred to as photoelectrons in this context The effect is also termed the Hertz EffectThe photoelectric effect takes place with photons with energies from about a few electronvolts to in some cases over 1 MeV184 Introduction and early historical view

With James Clerk Maxwells wave theory of light which was thought to predict that the electron energy would be proportional to the intensity of the radiation In 1905 Einstein solved this apparent paradox by describing light as composed of discrete quanta now called photons rather than continuous waves

15

A photon above a threshold frequency has the required energy to eject a single electron creating the observed effect This discovery led to the quantum revolution in physics and earned Einstein the Nobel Prize in 1921185 Traditional explanation

In the photoemission process if an electron within some material absorbs the energy of one photon and thus has more energy than the work function (the electron binding energy) of the material it is ejected If the photon energy is too low the electron is unable to escape the material Increasing the intensity of the light beam increases the number of photons in the light beam and thus increases the number of electrons emitted but does not increase the energy that each electron possesses Thus the energy of the emitted electrons does not depend on the intensity of the incoming light but only on the energy of the individual photonsAccording to Einsteins special theory of relativity the relation between energy (E) and momentum (p) of a particle is where m is the rest mass of the particle and c is the velocity of light in a vacuumIn 1887 Heinrich Hertz observed the photoelectric effect and the production and reception of electromagnetic (EM) waves His receiver consisted of a coil with a spark gap where a spark would be seen upon detection of EM waves He placed the apparatus in a darkened box to see the spark better However he noticed that the maximum spark length was reduced when in the box A glass panel placed between the source of EM waves and the receiver absorbed ultraviolet radiation that assisted the electrons in jumping across the gap When removed the spark length would increase He observed no decrease in spark length when he substituted quartz for glass as quartz does not absorb UV radiation Hertz concluded his months of investigation and reported the results obtained186Stoletov the first law of photoeffect

Stoletov invented a new experimental setup which was more suitable for a quantitative analysis of photoeffectHe discovered the direct proportionality between the intensity of light and the induced photo electric current (the first law of photoeffect or Stoletovs law)He found the existence of an optimal gaspressure Pm corresponding to a maximum photocurrent this property was used for a creation of solar cellsIn 1902 Philipp Lenard observed the variation in electron energy with light frequencyHe found the electron energy by relating it to the maximum stopping potential (voltage) in a phototube He found that the calculated maximum electron kinetic energy is determined by the frequency of the light For example an increase in frequency results in an increase in the maximum kinetic energy calculated for an electron upon liberation - ultraviolet radiation would require a higher applied stopping potential to stop current in a phototube than blue lightThe current emitted by the surface was determined by the lights intensity or brightness doubling the intensity of the light doubled the number of electrons emitted from the surface Lenard did not know of photons

16

187 Einstein light quanta

Assuming that Hertzian oscillators could only exist at energies E proportional to the frequency f of the oscillator by E = hf where h is Plancks constantIt explained why the energy of photoelectrons were dependent only on the frequency of the incident light and not on its intensity a low intensity high-frequency source could supply a few high energy photons whereas a high intensity low-frequency source would supply no photons of sufficient individual energy to dislodge any electronsEinsteins work predicted that the energy of individual ejected electrons increases linearly with the frequency of the lightBy 1905 it was known that the energy of photoelectrons increases with increasing frequency of incident light and is independent of the intensity of the light188 Uses and effectsThe photocathode contains combinations of materials such as caesium rubidium and antimony specially selected to provide a low work function so when illuminated even by very low levels of light the photocathode readily releases electronsPhotomultipliers are still commonly used wherever low levels of light must be detectedSilicon image sensors such as charge-coupled devices widely used for photographic imaging are based on a variant of the photoelectric effect in which photons knock electrons out of the valence band of energy states in a semiconductor but not out of the solid itself

The gold leaf electroscope

The electroscope is an important tool in illustrating the photoelectric effectshining high-frequency light onto the cap the scope discharges and the leaf will fall limpThe frequency of the light shining on the cap is above the caps threshold frequency The photons in the light have enough energy to liberate electrons from the cap reducing its negative charge189 Photoelectron spectroscopy

17

Photoelectron spectroscopy is done in a high-vacuum environment since the electrons would be scattered by significant numbers of gas atoms present (eg even in low-pressure air)The photoelectric effect will cause spacecraft exposed to sunlight to develop a positive charge This can get up to the tens of voltsThe static charge created by the photoelectric effect is self-limiting though because a more highly-charged object gives up its electrons less easily1810 Cross sectionThe photoelectric effect is simply an interaction mechanism conducted between photons and atoms However this mechanism does not have exclusivity in interactions of this nature and is one of 12 theoretically possible interactions The probability of the photoelectric effect occurring is measured by the cross section of interaction σ This has been found to be a function of the atomic number of the target atom and photon energy A crude approximation for photon energies above the highest atomic binding energy is given by Where n is a number which varies between 4 and 5

1811Electromagnetic units are part of a system of electrical units based primarily upon the magnetic properties of electric currents the fundamental SI unit being the ampere The units areAmpere (current)Coulomb (charge)Farad (capacitance)Henry (inductance)Ohm (resistance)Volt (electric potential)Watt (power)Tesla (magnetic field)In the electromagnetic system electrical current is a fundamental quantity defined via Ampegraveres law and takes the permeability as a dimensionless quantity (relative permeability) whose value in a vacuum is unity1812 Electromagnetic phenomenaWith the exception of gravitation electromagnetic phenomena as described by quantum electrodynamics account for almost all physical phenomena observable to the unaided human senses including light and other electromagnetic radiation all of chemistry most of mechanics (excepting gravitation) and of course magnetism and electricity1813 Electronic devices and circuitsEnergy bands in silicon intrinsic and extrinsic silicon Carrier transport in silicon diffusion current drift current mobility resistivity Generation and recombination of carriers p-n junction diode Zener diode tunnel diode BJT JFET MOS capacitor MOSFET LED p-i-n and avalanche photo diode LASERs Device technology integrated circuit fabrication process oxidation diffusion ion implantation photolithography n-tub p-tub and twin-tub CMOS process1814 Analog circuits Equivalent circuits (large and small-signal) of diodes BJTs JFETs and MOSFETs Simple diode circuits clipping clamping rectifier Biasing and bias stability of transistor and FET amplifiers Amplifiers single-and multi-stage differential operational feedback and power Analysis of amplifiers frequency response of amplifiers Simple op-amp circuits Filters Sinusoidal

18

oscillators criterion foroscillation single-transistor and op-amp configurations Function generators and waveshaping circuits Power supplies1815 Digital circuits of Boolean functions logic gates digital IC families (DTL TTL ECL MOS CMOS) Combinational circuits arithmetic circuits code converters multiplexers and decoders Sequential circuits latches and flip-flops counters and shift-registersSample and hold circuits ADCs DACs Semiconductor memories Microprocessor 8086 architecture programming memory and IO interfacing2 Signal processing TelecommunicationsEngineering amp Control engineering

It deals with the analysis and manipulation of signals Signals can be either analog in which case the signal varies continuously according to the information or digital in which case the signal varies according to a series of discrete values representing the information21Signal processing is an area of applied mathematics that deals with operations on or analysis of signals in either discrete or continuous time to perform useful operations on those signals Depending upon the application a useful operation could be control data compression data transmission denoising prediction filtering smoothing deblurring tomographic reconstruction identification classification or a variety of other operationsSignals of interest can include sound images time-varying measurement values and sensor data for example biological data such as electrocardiograms control system signals telecommunication transmission signals such as radio signals and many others22 Categories of signal processing Analog signal processing mdash for signals that have not been digitized as in classical radio telephone radar and television systems This involves linear electronic circuits such as passive filters active filters additive mixers integrators and delay lines It also involves non-linear circuits such as compandors multiplicators (frequency mixers and voltage-controlled amplifiers) voltage-controlled filters voltage-controlled oscillators and phase-locked loopsAnalog discrete-time signal processing is a technology based on electronic devices such as sample and hold circuits analog time-division multiplexers analog delay lines and analog feedback shift registersDigital signal processing mdash for signals that have been digitized Processing is done by general-purpose computers or by digital circuits such as ASICs fieldprogrammable gate arrays or specialized digital signal processors (DSP chips)Typical arithmetical operations include fixed-point and floating-point real-valued and complex-valued multiplication and addition Other typical operations supported by the hardware are circular buffers and look-up tables Examples of algorithms are the Fast Fourier transform (FFT) finite impulse response (FIR) filter Infinite impulse response (IIR) filter Wiener filter and Kalman filterFor analog signals signal processing may involve the amplification and filtering of audio signals for audio equipment or the modulation and demodulation of signals for telecommunications For digital signals signal processing may involve the compression error checking and error detection of digital signals

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23 Telecommunications engineeringIt deals with the transmission of information across a channel such as a co-axial cable optical fiber or free spaceTransmissions across free space require information to be encoded in a carrier wave in order to shift the information to a carrier frequency suitable for transmission this is known as modulation Popular analog modulation techniques include amplitude modulation and frequency modulation The choice of modulation affects the cost and performance of a system and these two factors must be balanced carefully by the engineerOnce the transmission characteristics of a system are determined telecommunication engineers design the transmitters and receivers needed for such systems These two are sometimes combined to form a two-way communication device known as a transceiverTelecommunications is a diverse field of engineering including electronics civil structural and electrical engineering as well as being a political and social ambassador a little bit of accounting and a lot of project managementTelecom engineers are often expected as most engineers are to provide the best solution possible for the lowest cost to the company24 Telecom equipment engineerA telecom equipment engineer is an electronics engineer that designs equipment such as routers switches multiplexers and other specialized computerelectronics equipment designed to be used in the telecommunication network infrastructureAs electrical engineers OSP engineers are responsible for the resistance capacitance and inductance (RCL) design of all new plant to ensure telephone service is clear and crisp and data service is clean as well as reliable Attenuation and loop loss calculations are required to determine cable length and size required to provide the service called forAs civil engineers OSP egineers are responsible for drawing up plans either by hand or using Computer Aided Drafting (CAD) software for how telecom plant facilities will be placed Often when working with municipalities trenching or boring permits are required and drawings must be made for theseStructural calculations are required when boring under heavy traffic areas such as highways or when attaching to other structures such as bridgesAs Political and Social Ambassador the OSP Engineer is the telephone operating companiesrsquo face and voice to the local authorities and other utilities25 Control engineering

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Control systems play a critical role in space flight

Control engineering is the engineering discipline that applies control theory to design systems with predictable behaviors The engineering activities focus on the mathematical modeling of systems of a diverse natureControl engineering has an essential role in a wide range of control systems from a simple household washing machine to a complex high performance F-16 fighter aircraftThe scope of classical control theory is limited to single-input and single-output (SISO) system designIn contrast modern control theory is strictly carried out in complex-s domain or in frequency domain and can deal with multi-input and multioutput (MIMO) systemsToday many of the control systems are computer controlled and they consist of both digital and analogue componentsThe first of these two methods is more commonly encountered in practice because many industrial systems have many continuous systems components including mechanical fluid biological and analogue electrical components with a few digital controllers

26 Instrumentation Engineering ampComputer EngineeringThe design of instrumentation requires a good understanding of physics that often extends beyond electromagnetic theory For example radar guns use the Doppler effect to measure the speed of oncoming vehicles Similarly thermocouples use the Peltier- Seebeck effect to measure the temperature difference between two pointsInstrumentation engineering is often viewed as the counterpart of control engineering

Pneumatic PID controller

Instrumentation is the branch of engineering that deals with measurement and controlAn instrument is a device that measures or manipulates variables such as flow temperature level or pressure Instruments include many varied contrivances

21

which can be as simple as valves and transmitters and as complex as analyzersThe control of processes is one of the main branches of applied instrumentationIn addition to measuring field parameters instrumentation is also responsible for providing the ability to modify some field parametersTo control the parameters in a process or in a particular system Microprocessors Microcontrollers PLCs etc are used But their ultimate aim is to control the parameters of a system27 Computer Systems Engineering) is a discipline that combines both Electrical Engineering and Computer Science Computer engineers may also work on a systems softwareThe design of complex software systems is often the domain of software engineering which is usually considered a separate disciplineComputer engineers usually have training in electrical engineering software design and hardware-software integration instead of only software engineering or electrical engineering Usual tasks involving computer engineers include writing software and firmware for embedded microcontrollers designing VLSI chips designing analog sensors designing mixed signal circuit boards and designing operating systems Computer engineers are also suited for robotics research which relies heavily on using digital systems to control and monitor electrical systems like motors communications and sensors28 AlgorithmAlgorithm is a finite sequence of instructions logic an explicit step-by-step procedure for solving a problem often used for calculation and data processing and many other fieldsThe transition from one state to the next is not necessarily deterministic some algorithms known as probabilistic algorithms incorporate randomnessA prototypical example of an algorithm is Euclids algorithm to determine the maximum common divisor of two integers (X and Y) which are greater than one We follow a series of steps In step i we divide X by Y and find the remainder which we call R1 Then we move to step i + 1 where we divide Y by R1 and find the remainder which we call R2 If R2=0 we stop and say that R1 is the greatest common divisor of X and Y If not we continue until Rn=0 Then Rn-1 is the max common division of X and YWe might expect an algorithm to be an algebraic equation such as y = m + n mdash two arbitrary input variables m and n that produce an output yThe concept of algorithm is also used to define the notion of decidabilityIn logic the time that an algorithm requires to complete cannot be measured as it is not apparently related with our customary physical dimension29 FormalizationAlgorithms are essential to the way computers process informationAn algorithm can be considered to be any sequence of operations that can be simulated by a Turing-complete systemAccording to Savage [1987] an algorithm is a computational process defined by a Turing machine (Gurevich 20003Typically when an algorithm is associated with processing information data is read from an input source written to an output device andor stored for further processingFor any such computational process the algorithm must be rigorously definedThe criteria for each case must be clear (and computable)

22

210 Expressing algorithmsAlgorithms can be expressed in many kinds of notation including natural languages pseudocode flowcharts and programming languages Natural language expressions of algorithms tend to be verbose and ambiguous and are rarely used for complex or technical algorithmsProgramming languages are primarily intended for expressing algorithms in a form that can be executed by a computer but are often used as a way to define or document algorithmsRepresentations of algorithms are generally classed into three accepted levels of Turing machine description (Sipser 2006157)1 High-level descriptionprose to describe an algorithm ignoring the implementation details At this level we do not need to mention how the machine manages its tape or head2 Implementation descriptionprose used to define the way the Turing machine uses its head and the way that it stores data on its tape At this level we do not give details of states or transition function3 Formal descriptionMost detailed lowest level gives the Turing machines state table For an example of the simple algorithm Add m+n described in all three levels211 Computer algorithmsIn computer systems an algorithm is basically an instance of logic written in software by software developers to be effective for the intended target computer(s) in order for the software on the target machines to do something For instance if a person is writing software that is supposed to print out a PDF document located at the operating system folder My Documents at computer drive D every Friday at 10PM they will write an algorithm that specifies the following actionsMost algorithms are intended to be implemented as computer programs However algorithms are also implemented by other means such as in a biological neural network (for example the human brain implementing arithmetic or an insect looking for food) in an electrical circuit or in a mechanical device212 Algorithmic analysisMethods have been developed for the analysis of algorithms to obtain such quantitative answers for example the algorithm above has a time requirement of O(n) using the big O notation with n as the length of the list At all times the algorithm only needs to remember two values the largest number found so far and its current position in the input list Therefore it is said to have a space requirement of O(1) if the space required to store the input numbers is not counted or O(n) if it is counted Different algorithms may complete the same task with a different set of instructions in less or more time space or effort than othersThe analysis and study of algorithms is a discipline of computer science and is often practiced abstractly without the use of a specific programming language or implementation In this sense algorithm analysis resembles other mathematical disciplines in that it focuses on the underlying properties of the algorithm and not on the specifics of any particular implementationIterative algorithms use repetitive constructs like loops and sometimes additional data structures like stacks to solve the given problems

23

Logical An algorithm may be viewed as controlled logical deduction This notion may be expressed as Algorithm = logic + control (Kowalski 1979) The logic component expresses the axioms that may be used in the computation and the control component determines the way in which deduction is applied to the axioms This is the basis for the logic programming paradigmAlgorithms are usually discussed with the assumption that computers execute one instruction of an algorithm at a timeParallel or distributed algorithms divide the problem into more symmetrical or asymmetrical subproblems and collect the results back togetherThe resource consumption in such algorithms is not only processor cycles on each processor but also the communication overhead between the processorsClassificationThere are various ways to classify algorithms each with its own meritsBy implementationOne way to classify algorithms is by implementation meansRecursion or iteration A recursive algorithm is one that invokes (makes reference to) itself repeatedly until a certain condition matches which is a method common to functional programmingSome problems are naturally suited for one implementation or the other For example towers of Hanoi is well understood in recursive implementationLogical An algorithm may be viewed as controlled logical deduction This notion may be expressed as Algorithm = logic + control (Kowalski 1979)In pure logic programming languages the control component is fixed and algorithms are specified by supplying only the logic componentSerial or parallel or distributed Algorithms are usually discussed with the assumption that computers execute one instruction of an algorithm at a timeThose computers are sometimes called serial computers An algorithm designed for such an environment is called a serial algorithm as opposed to parallel algorithms or distributed algorithmsThe greedy methodThe greedy method extends the solution with the best possible decision (not all feasible decisions) at an algorithmic stage based on the current local optimum and the best decision (not all possible decisions) made in a previous stage It is not exhaustive and does not give accurate answer to many problems But when it works it will be the fastest methodWhen solving a problem using linear programming specific inequalities involving the inputs are found and then an attempt is made to maximize (or minimize) some linear function of the inputsReduction This technique involves solving a difficult problem by transforming it into a better known problem for which we have (hopefully) asymptotically optimal algorithms This technique is also known as transform and conquerBy field of studyEvery field of science has its own problems and needs efficient algorithmsDynamic programming was originally invented for optimization of resource consumption in industry but is now used in solving a broad range of problems in many fieldsBy complexityAlgorithms can be classified by the amount of time they need to complete compared to their input size There is a wide variety some problems may have multiple algorithms of differing